[Pacemaker] pcs: Return code handling not clean

[Andrew Beekhof]

On 17/04/2013, at 8:33 AM, Chris Feist <cfeist at redhat.com> wrote:

> On 04/16/13 06:46, Andreas Mock wrote:
>> Hi all,
>> 
>> as I don't really know, where to address this
>> issue, I do post it here. On the one handside
>> as an information for guys scripting with the
>> help of 'pcs' and on the other handside with
>> the hope that one maintainer is listening
>> and will have a look at this.
>> 
>> Problem: When cluster is down a 'pcs resource'
>> shows an error message coming from a subprocess
>> call of 'crm_resource -L' but exits with an
>> error code of 0. That's something which can
>> be improved. Especially while the python code
>> does have error handling in other paces.
>> 
>> So I guess it is a simple oversight.
>> 
>> Look at the following piece of code in
>> pcs/resource.py:
>> 
>> 915     if len(argv) == 0:
>> 916         args = ["crm_resource","-L"]
>> 917         output,retval = utils.run(args)
>> 918         preg = re.compile(r'.*(stonith:.*)')
>> 919         for line in output.split('\n'):
>> 920             if not preg.match(line) and line != "":
>> 921                 print line
>> 922         return
>> 
>> retval is totally ignored, while being handled on
>> other places. That leads to the fact that the script
>> returns with status 0.
> 
> This is an oversight on my part, I've updated the code to check retval and return an error.  Currently I'm not passing through the full error code (I'm only returning 0 on success and 1 on failure).  However, if you think it would be useful to have this information I would be happy to look at it and see what I can do.  I'm planning on eventually having pcs interpret the crm_resource error code and provide a more user friendly output instead of just a return code.

there is a crm_perror binary that might be useful for this

> 
> Thanks,
> Chris
> 
>> 
>> Interestingly the error handling of the utils.run call
>> used all over the module is IMHO a little bit inconsistent.
>> If I remember correctly Andrew did some efforts in the
>> past to have a set of return codes comming from the
>> base cibXXX and crm_XXX tools. (I really don't know
>> how much they are differentiated). Why not pass them
>> through?
>> 
>> Best regards
>> Andreas Mock
>> 
>> 
>> 
>> 
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> 
> 
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